Many devices and methods utilizing various surgical instruments such as scissors, forceps and the like have been developed over the years for use in surgical operations. Often, the configuration and construction of the surgical instruments have been based on anatomical considerations as well as on the importance of providing a surgeon with tactile information important in achieving proper control over the instrument. Visual aids such as fluoroscopy, x-radiography and fiberoptics are often used, however a surgeon manipulating such an instrument must nevertheless rely on tactile sensitivity to locate, grasp, cut and remove the desired tissue.
Endoscopic instruments have been extensively utilized by surgeons to provide an internal view of an organ, body passage or lumen requiring treatment. Many of these instruments are specially made to include fiberoptic assemblies within their structure. Because of the internal mounting of the fiberoptic assemblies together with flushing and access passageways, such endoscopic instruments tend to be relatively large in diameter, limiting their uses.
Some of these instruments are rigid endoscopes that have a working element or tool located at their distal ends. Such rigid endoscopes provide excellent optical images, but they often suffer from several drawbacks. They require precise alignment and are therefore fairly expensive to manufacture. The optical systems employed do not allow the endoscopes to be bent and this necessarily limits the ability of the surgeon to gain access to many areas of the body to be worked on. Also, a video camera must be clamped onto the proximal end of the endoscope so that the surgeon must hold the camera's weight. This will limit the tactile feel.
One such example is U.S. Pat. No. 5,089,000 to Agee which discloses a surgical instrument for manipulating selected tissue in a body cavity. The Agee device includes a hollow sheath mounted on a complicated handle assembly. The result is a large and bulky instrument with limited tactile feel for the surgeon. Further, the Agee device is straight which limits its access to many areas of the body.
A flexible endoscope, on the other hand, provides access to parts of the body that are not accessible with rigid instruments. The surgeon may pass a flexible tool through a working channel in the endoscope to manipulate tissue at the distal end of the endoscope. With a flexible endoscope, however, it becomes difficult to position the working end, when it is considered that the equal and opposite reaction to a force may easily push the end of a flexible endoscope away from the target tissue.
One attempt to combine flexible and rigid systems is U.S. Pat. No. 4,300,564 to Furihata. The Furihata device uses a relatively large tubular member mounted on the handle of an instrument. The tubular member extends away from the handle of the instrument at an angle and includes a fluid port connected to the tubular member. An endoscope can be inserted in the tubular member but there is no provision for fixing the endoscope such that a predetermined field-of-view for the working end is provided. As will be readily understood, such a design does not provide for good tactile feel particularly when a suction or flushing source is connected to the fluid port.
Another design, such as shown in U.S. Pat. No. 4,759,348 to Cawood uses an externally mounted endoscope on the surgical instrument. Cawood uses an endoscope assembly with a distal optical head equipped with a connector for externally and releasably attaching the head to the neck of a surgical instrument adjacent the distal end of the instrument.
Only the endoscope's optical head is releasably clipped to the distal end of the Cawood surgical instrument. The clip-on head is secured to the surgical instrument just before the surgical procedure in an attempt to make it possible for the surgeon to view the working tip of the instrument. Because of the design, proper alignment and focusing on the working tip of the instrument can be time consuming and frustrating. Because Cawood only connects the endoscope to the distal end of the instrument, there is no provision for the endoscope to have its body follow or conform to the shape of the instrument. Also, the endoscope may come into unwanted contact with surrounding tissue where it is in the body but not attached to the instrument. With such a design, the weight and flexibility of the endoscope can dampen the tactile feel which is so important to a surgeon, and essential to an efficient and successful surgical procedure.
A surgical device whose distal end cannot be precisely maneuvered tends to interrupt a surgeon's tactile feel and ability to control the working element of the instrument and the tissue being manipulated. Moreover, the clip on the Cawood device can provide an obstacle in a surgeon's field-of-view around the endoscope. The size of such an assembly as proposed by Cawood requires a larger than necessary incision to allow entry of the endoscope, the clip, and the surgical tool through the same opening.
In most if not all of these prior instruments, a surgeon's hands are spaced well away from the distal end of the endoscope or instrument which limits the surgeon's precise and accurate control of the distal end of the endoscope or instrument, and the tactile sensitivity. What is needed is a new design which provides an accurate and clear view of the surgical site and the distal operating portion of the surgical instrument. Such a device should also provide for maximizing tactile feedback and sensitivity to locate, grasp, cut and remove the desired tissue. The device should also be small in cross-section to provide for easy access to the tissue and improved tactile feel. The present invention meets these desires.